Problem: Ishaan eats at a restaurant and the cost of his meal is $\$25.00$. He would like to leave a $15\%$ tip. What is his total bill including tip?
Answer: The tip amount is equal to $15\% \times \$25.00$ We can find the tip by first calculating a $10\%$ tip and a $5\%$ tip, and then adding those two numbers together. To calculate a $10\%$ tip, move the decimal point in $\$25.00$ one place to the left. $10\%$ $\times \$25.00$ $\$2.50$ To calculate a $5\%$ tip, divide the $10\%$ tip amount in half. $5\%$ $\times \$25.00 = $ $\$2.50$ $ \div 2 = $ $\$1.25$ Adding the two amounts together gives us $\$2.50$ $\$1.25 =$ $ \$3.75$ The cost of the meal plus the amount of the tip will equal the total bill amount. $\$25.00 + \$3.75 = $ $\$28.75$ The total cost of the bill is $\$28.75$.